1. Field of the Invention
The present invention relates to a video outputting method and device. More particularly, the present invention relates to a video outputting method and device capable of causing a display device to display images with acceptable quality without flickers.
2. Description Related to the Prior Art
There are electronic images with various aspect ratios. Among those, a standard image has a standard aspect ratio of 4/3, and a widescreen (wide) image has a widescreen (wide) aspect ratio of 16/9, which is horizontally longer than the standard aspect ratio. The format of the widescreen image is widely used in video software and broadcast of high-vision or wide clear vision. Video outputting devices, such as suggested in JP-A 4-091572 and JP-A 6-268932, have compatibility, and output video signals to a camera, video player, and a widescreen (wide) display device of which a format is the widescreen aspect ratio. The use of the widescreen aspect ratio has remarkably been spread.
To output a video signal of the widescreen image, upper and lower blank masked regions are added by the video outputting device to image data, to convert an aspect ratio to the standard aspect ratio. Thus, the video outputting device can output video signal in a suitable form to a standard display device having the standard aspect ratio and the widescreen display device.
A conventional type of the standard display device is not suitable for the use of the widescreen image. An error is likely to occur in the standard display device if receiving data of the widescreen image. However, outputting of a video signal of the widescreen image at the standard aspect ratio is effective in reception of the widescreen image by way of the standard image. The standard display device displays an image on its display region in an unchanged form of the video signal. Therefore, the aspect ratio of the display region for the standard image is equal to that of the standard image. Upon reception of the signal of the standard image, the standard image is displayed fully by use of the display region of the standard display device. Upon reception of the signal of the widescreen image, the widescreen image together with the upper and lower blank masked regions is displayed on the display region according to the video signal.
The widescreen display device is constructed to check existence or lack of the upper and lower blank masked regions in response to a video signal, and discerns the widescreen image from the standard image. In case of the widescreen image, the upper and lower blank masked regions are cut away in the widescreen display device to set an aspect ratio according to the video signal equal to that of the display region. Therefore, the widescreen image appears fully in the display region.
Furthermore, digital still cameras has been widely used in recent years. Each of the digital still camera is provided with a video output terminal, which outputs a video signal of an image to a display panel disposed on the rear of a camera body for displaying images on the display panel. If an external display device disconnected with the video output terminal, the camera user is enabled to observe various image by use of the display region of a large side on the external display device.
However, the widescreen display device requires data processing for discernment of the widescreen image from the standard image for the purpose of the displaying operation. If a slide show is desired by outputting of a sequence of plural images including irregularly arranged sets of the standard image and the widescreen image, delay in the processing is likely to cause flickers on the display region, which cannot be watched in an acceptably comfortable manner during the intermediate periods between plural images.